/**
 * Software License, Version 1.0
 * 
 * Copyright 2008 The Trustees of Indiana University.  All rights reserved.
 * 
 *
 *Redistribution and use in source and binary forms, with or without 
 *modification, are permitted provided that the following conditions are met:
 *
 *1) All redistributions of source code must retain the above copyright notice,
 * the list of authors in the original source code, this list of conditions and
 * the disclaimer listed in this license;
 *2) All redistributions in binary form must reproduce the above copyright 
 * notice, this list of conditions and the disclaimer listed in this license in
 * the documentation and/or other materials provided with the distribution;
 *3) Any documentation included with all redistributions must include the 
 * following acknowledgment:
 *
 *"This product includes software developed by the Community Grids Lab. For 
 * further information contact the Community Grids Lab at 
 * http://communitygrids.iu.edu/."
 *
 * Alternatively, this acknowledgment may appear in the software itself, and 
 * wherever such third-party acknowledgments normally appear.
 * 
 *4) The name Indiana University or Community Grids Lab or Granules, 
 * shall not be used to endorse or promote products derived from this software 
 * without prior written permission from Indiana University.  For written 
 * permission, please contact the Advanced Research and Technology Institute 
 * ("ARTI") at 351 West 10th Street, Indianapolis, Indiana 46202.
 *5) Products derived from this software may not be called Granules, 
 * nor may Indiana University or Community Grids Lab or Granules appear
 * in their name, without prior written permission of ARTI.
 * 
 *
 * Indiana University provides no reassurances that the source code provided 
 * does not infringe the patent or any other intellectual property rights of 
 * any other entity.  Indiana University disclaims any liability to any 
 * recipient for claims brought by any other entity based on infringement of 
 * intellectual property rights or otherwise.  
 *
 * LICENSEE UNDERSTANDS THAT SOFTWARE IS PROVIDED "AS IS" FOR WHICH NO 
 * WARRANTIES AS TO CAPABILITIES OR ACCURACY ARE MADE. INDIANA UNIVERSITY GIVES
 * NO WARRANTIES AND MAKES NO REPRESENTATION THAT SOFTWARE IS FREE OF 
 * INFRINGEMENT OF THIRD PARTY PATENT, COPYRIGHT, OR OTHER PROPRIETARY RIGHTS. 
 * INDIANA UNIVERSITY MAKES NO WARRANTIES THAT SOFTWARE IS FREE FROM "BUGS", 
 * "VIRUSES", "TROJAN HORSES", "TRAP DOORS", "WORMS", OR OTHER HARMFUL CODE.  
 * LICENSEE ASSUMES THE ENTIRE RISK AS TO THE PERFORMANCE OF SOFTWARE AND/OR 
 * ASSOCIATED MATERIALS, AND TO THE PERFORMANCE AND VALIDITY OF INFORMATION 
 * GENERATED USING SOFTWARE.
 */
package cgl.granules.exchange;

import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.IOException;

import cgl.granules.exception.MarshallingException;
import cgl.granules.scheduler.TaskLifecycleMetrics;
import cgl.granules.util.MarshallingUtil;

/**
 * This class encapsulates exchanges related to retrieving the status of a
 * message.
 * 
 * @author Shrideep Pallickara
 * 
 */
public class ExecutionStatus extends Exchange {
	private String jobIdentifier;

	private String taskIdentifier;

	private TaskLifecycleMetrics taskLifecycleMetrics;

	protected ExecutionStatus() {
	}

	protected ExecutionStatus(String jobIdentifier, String taskIdentifier,
			String respondTo) {
		if (jobIdentifier == null) {
			throw new NullPointerException("Specified JobIdentifier is NULL");
		}
		if (taskIdentifier == null) {
			throw new NullPointerException("Specified TaskIdentifier is NULL");
		}
		if (respondTo == null) {
			throw new NullPointerException("Specified RespondTo stream is NULL");
		}

		this.jobIdentifier = jobIdentifier;
		this.taskIdentifier = taskIdentifier;

		setExchangeType(ExchangeType.EXECUTION_STATUS);
		setRequest();
		setRespondTo(respondTo);
	}

	protected ExecutionStatus(String jobIdentifier, String taskIdentifier,
			int conditionFlag, String description,
			TaskLifecycleMetrics taskLifecycleMetrics, String respondTo) {
		if (jobIdentifier == null) {
			throw new NullPointerException("Specified JobIdentifier is NULL");
		}
		if (taskIdentifier == null) {
			throw new NullPointerException("Specified TaskIdentifier is NULL");
		}
		if (conditionFlag != ConditionFlag.PROBLEMS_ENCOUNTERED) {
			if (taskLifecycleMetrics == null) {
				throw new NullPointerException("Specified Metrics is NULL");
			}
		}
		this.jobIdentifier = jobIdentifier;
		this.taskIdentifier = taskIdentifier;
		this.taskLifecycleMetrics = taskLifecycleMetrics;

		setRespondTo(respondTo);
		setExchangeType(ExchangeType.EXECUTION_STATUS);
		setResponse();
		setDescription(description);
		setConditionFlag(conditionFlag);
	}

	@Override
	public boolean isValidExchangeSubType() {
		return true;
	}

	/**
	 * @return the jobIdentifier
	 */
	public String getJobIdentifier() {
		return jobIdentifier;
	}

	/**
	 * 
	 * @return the taskIdentifier
	 */
	public String getTaskIdentifier() {
		return taskIdentifier;
	}

	/**
	 * Retrieve the <code>TaskLifecycleMetrics</code> associated with the
	 * RESPONSE.
	 * 
	 * @return The taskLifecycle metrics for a task.
	 */
	public TaskLifecycleMetrics getTaskLifecycleMetrics() {
		return taskLifecycleMetrics;
	}

	@Override
	public byte[] marshallExchangeSpecificElements() throws IOException,
			MarshallingException {
		byte[] marshalledBytes = null;
		ByteArrayOutputStream baOutputStream = new ByteArrayOutputStream();
		DataOutputStream dout = new DataOutputStream(new BufferedOutputStream(
				baOutputStream));
		MarshallingUtil marshaller = MarshallingUtil.getInstance();

		marshaller.writeString(dout, jobIdentifier);
		marshaller.writeString(dout, taskIdentifier);

		if (isResponse()) {
			if (getConditionFlag() != ConditionFlag.PROBLEMS_ENCOUNTERED) {
				byte[] metricBytes = taskLifecycleMetrics.getBytes();
				dout.writeInt(metricBytes.length);
				dout.write(metricBytes);
			}
		}

		/** check to see if this is a request or response and do accordingly */
		dout.flush();
		marshalledBytes = baOutputStream.toByteArray();
		return marshalledBytes;
	}

	@Override
	public void unmarshallExchangeSpecificElements(byte[] exchangeSpecificBytes)
			throws IOException, MarshallingException {
		ByteArrayInputStream baInputStream = new ByteArrayInputStream(
				exchangeSpecificBytes);
		DataInputStream din = new DataInputStream(new BufferedInputStream(
				baInputStream));
		MarshallingUtil marshaller = MarshallingUtil.getInstance();

		jobIdentifier = marshaller.readString(din);
		taskIdentifier = marshaller.readString(din);
		if (isResponse()) {
			if (getConditionFlag() != ConditionFlag.PROBLEMS_ENCOUNTERED) {
				byte[] metricBytes = new byte[din.readInt()];
				din.readFully(metricBytes);
				taskLifecycleMetrics = new TaskLifecycleMetricsReader(
						metricBytes);
			}
		}
	}

	@Override
	public String toString() {
		String representation = "ExecutionStatus: ";

		if (isRequest()) {
			representation += "(Request)";
		}

		if (isResponse()) {
			representation += "(Response)";
		}

		representation += (" Job Identifier = " + jobIdentifier
				+ ", Task Identifier = " + taskIdentifier);

		if (getDescription() != null) {
			representation += ("  " + getDescription());
		}
		return representation;
	}

}
